If the pictures don't show up I can post them again, but one thing I have noticed was that not all fans are created equal. I was using the Sunon 40mm fans. Those were the fans I modded for extra strength. They all ended up with the fan blade assembly coming off the staff.

So I tried a different brand of fan. I tried the NMB-MAT brand of fan. They are more expensive but they seem to be stronger. They have what I think is metal in the center of the fan blade assembly. Which seem to help keep the fan on the shaft. They seem to be put together much better. In fact I couldn't get them apart to mod them without breaking them. I've only experimented with them so far, so I don't know how well they will survive in the long term though. I do know that they are much better then the Sunon fans.

I accidently stuck my finger in one of the fans and it took off a small chunk of finger nail and gave me a small cut. I was a little surprised. They might warrent having a guard on them.

You can get them at Digi key or Newark one. They are 12V @ $11.?? Model: 1604KL-04W-840

If anyone else has another brand that has been pretty tough please post which brand.

Can't seem to post these again. I get a message "You have already attached this file in thread: How to make your fans bullet proof." I tried changing the name with no luck. Anybody have any ideas?
One did work though.

Again, the NMB-MAT brand of fan is built better over all, You don't need to glue in the internals. The little supports need to be beefed up. They are a little thin. I took some small zip ties pieces and glued them with CA glue to the support to beef them up. The last picture is the NMB-MAT fan. I yellowed the area were the I glued the zip ties.

Yeah this has always been an issue for me as well. I said screw it and went to industrial fans on everything and haven't had one problem since. Technically the 25mm fans are the "right" size, but if you clock the 30mm a degree or two, they still allow you to screw to the heatsinks.

The 12V fans can get a little thicker 10mm - 15mm - 20mm, but mounting space has never been a problem. In this post you can see the thicker fan I used to keep the Tekin R1 cool. The thicker the fan box the more efficient it is and the more air it will move. The other cool thing is that you can plug a 12V fan right into a 4S pack without any problems and it will really keep things cool. I have been doing this for about a year now and have never had an issue. These 12V fans move loads more air than the crappy RC fans we usually have available to us and as you can see these are MUCH beefier.http://www.rc-monster.com/forum/show...808#post223808